An Amorphous Native Oxide Shell for High Bias-Stress Stability Nanowire Synaptic Transistor

The inhomogeneous native oxide shells on the surfaces of III-V group semiconductors typically yield inferior and unstable electrical properties metrics, challenging the development of next-generation integrated circuits. Herein, the native GaOx shells are profitably utilized by a simple in-situ thermal annealing process to achieve high-performance GaSb nanowires (NWs) field-effect-transistors (FETs) with excellent bias-stress stability and synaptic behaviors. By an optimal annealing time of 5 min, the as-constructed GaSb NW FET demonstrates excellent stability with a minimal shift of transfer curve (& UDelta;Vth & AP; 0.54 V) under a 60 min gate bias, which is far more stable than that of pristine GaSb NW FET (& UDelta;Vth & AP; 8.2 V). When the high bias-stress stability NW FET is used as the chargeable-dielectric free synaptic transistor, the typical synaptic behaviors, such as short-term plasticity, long-term plasticity, spike-time-dependent plasticity, and reliable learning stability are demonstrated successfully through the voltage tests. The mobile oxygen ion in the native GaOx shell strongly offsets the trapping states and leads to enhanced bias-stress stability and charge retention capability for synaptic behaviors. This work provides a new way of utilizing the native oxide shell to realize stable FET for chargeable-dielectric free neuromorphic computing systems. A tunable approach is reported first to manipulate the amorphous native GaOx shells of GaSb NWs via a simple in situ annealing process. Furthermore, these native GaOx shells are studied systematically for improving the bias-stress stability of the GaSb NWs FETs and broadening the application in chargeable-dielectric free synaptic transistors with typical synaptic behaviors and reliable learning stability.image

Automated summary

High-performance GaSb nanowire field-effect transistors (FETs) with excellent bias-stress stability and synaptic behaviors are achieved by utilizing native GaOx shells through in-situ thermal annealing. The native oxide shell provides enhanced stability and charge retention capability for synaptic behaviors.